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Bi-temporal texton forest for land cover transition detection on remotely sensed imagery / Zhen Lei in IEEE Transactions on geoscience and remote sensing, vol 52 n° 2 (February 2014)
[article]
Titre : Bi-temporal texton forest for land cover transition detection on remotely sensed imagery Type de document : Article/Communication Auteurs : Zhen Lei, Auteur ; Tao Fang, Auteur ; Hong Huo, Auteur ; Deren Li, Auteur Année de publication : 2014 Article en page(s) : pp 1227 - 1237 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] arbre de décision
[Termes IGN] détection de changement
[Termes IGN] gradient
[Termes IGN] occupation du solRésumé : (Auteur) With the advancement of machine learning, classification methods have been increasingly used in change (or transition) detection. The texton forest (TF)-based method has received increasing research attention because of its speed, good generalization characteristics, stability, and especially its ability to capture spatial contextual information. In this paper, we propose a TF-based method for transition detection in remotely sensed imagery. We investigate a maximal joint-information gain criterion for random forests to better capture combined information in the bi-temporal images in transition detection, which is implemented by a natural extension of binary-trees in traditional methods into a quad-decision tree structure. We also utilize color-invariant gradient as a feature to help alleviate the impact of difference in imaging conditions on bi-temporal transition detection. The experimental results for transition detection show that our bi-temporal TF classifier achieves better performance than a post-classification comparison method and several other alternative methods. Numéro de notice : A2014-075 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2013.2248738 En ligne : https://doi.org/10.1109/TGRS.2013.2248738 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32980
in IEEE Transactions on geoscience and remote sensing > vol 52 n° 2 (February 2014) . - pp 1227 - 1237[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2014021 RAB Revue Centre de documentation En réserve L003 Disponible A spectral gradient difference based approach for land cover change detection / Jun Chen in ISPRS Journal of photogrammetry and remote sensing, vol 85 (November 2013)
[article]
Titre : A spectral gradient difference based approach for land cover change detection Type de document : Article/Communication Auteurs : Jun Chen, Auteur ; Miao Lu, Auteur ; Xuehong Chen, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 1 - 12 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] appariement de formes
[Termes IGN] détection de changement
[Termes IGN] gradient
[Termes IGN] image Landsat-ETM+
[Termes IGN] image Landsat-TM
[Termes IGN] occupation du solRésumé : (Auteur) Change detection with remotely sensed imagery plays an important role in land cover mapping, process analysis and dynamic information services. Euclidean distance, correlation and other mathematic metrics between spectral curves have been used to calculate change magnitude in most change detection methods. However, many pseudo changes would also be detected because of inter-class spectral variance, which remains a significant challenge for operational remote sensing applications. In general, different land cover types have their own spectral curves characterized by typical spectral values and shapes. These spectral values are widely used for designing change detection algorithms. However, the shape of spectral curves has not yet been fully considered. This paper proposes to use spectral gradient difference (SGD) to quantitatively describe the spectral shapes and the differences in shape between two spectra. Change magnitude calculated in the new spectral gradient space is used to detect the change/no-change areas. Then, a chain model is employed to represent the SGD pattern both qualitatively and quantitatively. Finally, the land cover change types are determined by pattern matching with the knowledgebase of reference SGD patterns. The effectiveness of this SGD-based change detection approach was verified by a simulation experiment and a case study of Landsat data. The results indicated that the SGD-based approach was superior to the traditional methods. Numéro de notice : A2013-604 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2013.07.009 En ligne : https://doi.org/10.1016/j.isprsjprs.2013.07.009 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32740
in ISPRS Journal of photogrammetry and remote sensing > vol 85 (November 2013) . - pp 1 - 12[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2013111 RAB Revue Centre de documentation En réserve L003 Disponible Towards a 1 mGal accuracy and 1 min resolution altimetry gravity field / Lifeng Bao in Journal of geodesy, vol 87 n° 10-12 (October - December 2013)
[article]
Titre : Towards a 1 mGal accuracy and 1 min resolution altimetry gravity field Type de document : Article/Communication Auteurs : Lifeng Bao, Auteur ; Houze Xu, Auteur ; Zhicai Li, Auteur Année de publication : 2013 Article en page(s) : pp 961 - 969 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] altimétrie satellitaire par radar
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] géodésie marine
[Termes IGN] gradient
[Termes IGN] océanographie spatiale
[Termes IGN] surface de la merRésumé : (Auteur) Over the past three decades, radar altimetry has made a significant contribution to marine gravity field modeling. To improve the accuracy and resolution, we propose a new twin-satellite altimetry. Such a system has several advantages. Among others, it provides (i) twice the number of samples per time epoch, and (ii) information about the cross-track surface gradient with high accuracy because most of the environmental and tidal errors will be common to the simultaneous measurements and therefore cancel out when computing the cross-track gradient computation. We describe a rigorous procedure for the deduction of the sea surface gradient at each altimeter observation point (i.e., not only at the crossovers), from the twin-satellite altimetry system. The precision of the gradient will be slightly affected by orbit errors, instrument drift, and inaccuracies in the geophysical corrections to be applied. We also demonstrate that a 1 mGal accuracy and 1 min resolution marine altimetry gravity field can be obtained if certain conditions are met. To achieve the expected goal, we recommend an orbital configuration, phasing two satellites in 4-s time delay such that the Earth rotation creates a natural baseline between the two satellites, and a 18 kHz SAR altimeter. Numéro de notice : A2013-669 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-013-0660-1 Date de publication en ligne : 25/09/2013 En ligne : https://doi.org/10.1007/s00190-013-0660-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32805
in Journal of geodesy > vol 87 n° 10-12 (October - December 2013) . - pp 961 - 969[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2013101 SL Revue Centre de documentation Revues en salle Disponible Topological gradient connection analysis for feature detection / Chao-Yuan Lo in Photogrammetric record, vol 28 n° 141 (March - May 2013)
[article]
Titre : Topological gradient connection analysis for feature detection Type de document : Article/Communication Auteurs : Chao-Yuan Lo, Auteur ; Lieng-Chien Chen, Auteur Année de publication : 2013 Article en page(s) : pp 7 - 26 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse comparative
[Termes IGN] connexité (topologie)
[Termes IGN] détection de contours
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] filtre de Canny
[Termes IGN] gradient
[Termes IGN] ligne caractéristique
[Termes IGN] lissage de courbe
[Termes IGN] niveau de gris (image)
[Termes IGN] relation topologiqueRésumé : (Auteur) Edges and corners are two major image features in the modelling of man-made objects; an edge provides strong geometric orientation and corners possess good localisation. Feature detection is the basis of image processing for numerous applications such as image registration and object modelling. Completeness and localisation are the two major considerations for these applications; however, illumination, reflectance and shadows may interfere with image grey values to produce various gradients along an edge. Thus, threshold selection is an important step in obtaining suitable features in target-dependent methods as improper selection might cause information loss and broken edges. Instead of threshold selection, this study therefore proposes a feature extraction method using topological gradient connection (TGC) analysis involving three steps: grey value refinement, gradient computation and topological connection analysis. The first step uses a Gaussian filter to smooth the grey value image. The second step computes directional gradients to identify ridge pixels and collect feature candidates. The third step analyses adjacent candidates based on the criterion of topological connection. This three-step tracing procedure combines these connected candidates into a single object. The proposed scheme employs different images derived from various sensors and compares them with the Canny operator (using manually selected thresholds) and manually plotted corners for detection ability assessment. Experimental results indicate that the automatic results are more complete for subtle feature lines than the Canny edges. In addition, the proposed method provides higher flexibility in selecting suitable feature layers for different applications. Numéro de notice : A2013-149 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.2012.00703.x Date de publication en ligne : 16/12/2012 En ligne : https://doi.org/10.1111/j.1477-9730.2012.00703.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32287
in Photogrammetric record > vol 28 n° 141 (March - May 2013) . - pp 7 - 26[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 106-2013011 RAB Revue Centre de documentation En réserve L003 Disponible A variational gradient-based fusion method for visible and SWIR imagery / H. Li in Photogrammetric Engineering & Remote Sensing, PERS, vol 78 n° 9 (September 2012)
[article]
Titre : A variational gradient-based fusion method for visible and SWIR imagery Type de document : Article/Communication Auteurs : H. Li, Auteur ; L. Zhang, Auteur ; H. Shen, Auteur ; P. Li, Auteur Année de publication : 2012 Article en page(s) : pp 947 - 958 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] appariement d'images
[Termes IGN] débrumage
[Termes IGN] effet atmosphérique
[Termes IGN] fusion d'images
[Termes IGN] gradient
[Termes IGN] image Landsat-ETM+
[Termes IGN] image Landsat-SWIR
[Termes IGN] longueur d'ondeRésumé : (Auteur) This paper presents a new variational gradient-based fusion method for visible and short-wave infrared (swm) imagery. The proposed method enables spatial enhancement and dehazing of visible imagery. Integrating gradients from SWIR imagery into visible imagery produces a single image with true color and sharp gradients. A constraint based on band correlation is included to improve the enhancement and implement dehazing. The band correlation is according to the quantitative relationship between the wavelength and the atmospheric effect caused by Rayleigh scattering. In this study, both clear and hazy Landsat ETM+ images are used in the experiments. By visual assessment, the gradient of the fused image is more salient than that of the original image, and the true color is well preserved. With the inclusion of the band correlation constraint, the proposed fusion method yields almost haze-free results. Quantitatively, the Metric Q of the fused images is significantly higher than that of the original images; the largest increase of the Metric Q in the experimental results is from 0.0114 to 0.0611. Moreover, for the results of the proposed method, the Metric Q increase in the visible bands declines from blue band to red band. Numéro de notice : A2012-442 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.78.9.947 En ligne : https://doi.org/10.14358/PERS.78.9.947 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31888
in Photogrammetric Engineering & Remote Sensing, PERS > vol 78 n° 9 (September 2012) . - pp 947 - 958[article]Wind resource assessment from C-band SAR / M.B. Christiansen in Remote sensing of environment, vol 105 n° 1 (15/11/2006)PermalinkA robust technique for precise registration of radar and optical satellite images / T.D. Hong in Photogrammetric Engineering & Remote Sensing, PERS, vol 71 n° 5 (May 2005)PermalinkCalcul de l'allongement troposphérique via l'utilisation de cartes de l'ECMWF / Samuel Nahmani (2005)PermalinkFabrication de vraies ortho-images et correction des ombres / Didier Boldo in Bulletin d'information scientifique et technique de l'IGN, n° 74 (mars 2003)PermalinkAnalyse par ondelettes de processus localement dilatés et application au gradient de texture / Maureen Clerc Gallagher (1999)PermalinkSegmentation multi-échelle d'un modèle numérique de terrain / G. Dufourcq (1997)PermalinkContouring, a guide to the analysis and display of spatial data / David F. Watson (1994)PermalinkGeoid gradients for Geosat and Topex-Poseidon repeat ground tracks / Y.M. Wang (1991)PermalinkNoise and temperature gradients in multichannel sea surface temperature imagery of the ocean / P.E. La Violette in Remote sensing of environment, vol 25 n° 2 (01/07/1988)Permalink